package cn.tansanqinger.util;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Random;
import javax.imageio.ImageIO;
/**
* 该类用于验证码随机生成
*
* 相关使用案例
* @Test
 public void fun2() throws FileNotFoundException, IOException {
  VerifyCode vc = new VerifyCode();
  BufferedImage bi = vc.getImage();
  VerifyCode.output(bi, new FileOutputStream("F:/xxx.jpg"));//调用静态方法将文件保存到指定位置
  System.out.println(vc.getText());
 }
*
*/
public class VerificationUtil {
	private int w = 210 ; //设置宽度
	private int h = 70 ; //设置高度
	private Random r = new Random();
	//可选字体
	private String[] fontNames = {"宋体","华文楷体","黑体","微软雅黑","楷体_GB2312"};
	//可选字符
	private String codes = "23456789abcdefghjkmnopqrstuvwxyzABCDEFGHJKMNKQRSTUVWXYZ";
	//背景色
	private Color bgColor = new Color(255,255,255);
	//验证码上的文本
	private String text;
	//生成随机颜色
	private Color randomColor() {
		int red = r.nextInt(150);
		int green = r.nextInt(150);
		int blue = r.nextInt(150);
		return new Color(red,green,blue);
	}
	//生成随机字体
	private Font randomFont() {
		int index = r.nextInt(fontNames.length);
		String fontName = fontNames[index];
		int style = r.nextInt(4);//生成随机的样式，0表示无样式，1表示粗体，2表示斜体3表示粗体加斜体
		int size = r.nextInt(35)+25;//生成随机字号，25~70
		return new Font(fontName, style , size);
	}
	//画干扰线
	private void drawLine(BufferedImage image) {
		int num = 20 ;//一共画三条
		Graphics2D g2 = (Graphics2D) image.getGraphics();
		for(int i = 0 ; i < num ; i++) {//生成两个点的坐标
			int x1 = r.nextInt(w);
			int y1 = r.nextInt(h);
			int x2 = r.nextInt(w);
			int y2 = r.nextInt(h);
			g2.setStroke(new BasicStroke(1.5F));
			g2.setColor(Color.BLUE);//干扰线颜色
			g2.drawLine(x1, y1, x2, y2);//画线
		}
	}
	//随机生成一个字符
	private char randomChar() {
		int index = r.nextInt(codes.length());
		return codes.charAt(index);
	}
	//创建BufferedImage
	private BufferedImage createImage() {
		BufferedImage image = new BufferedImage(w, h , BufferedImage.TYPE_INT_RGB);
		Graphics2D g2 = (Graphics2D) image.getGraphics();
		g2.setColor(this.bgColor);
		g2.fillRect(0, 0, w, h);
		return image;
	}
	//调用这个方法得到验证码
	public BufferedImage getImage() {
		BufferedImage image = createImage();//创建图片缓冲区
		Graphics2D g2 = (Graphics2D) image.getGraphics();//得到绘制环境
		StringBuilder sb = new StringBuilder();//用来装载生成的验证码文本
		//向图片中画4个字符
		for(int i = 0 ; i < 6 ; i ++) {
			String s = randomChar()+"";//随机生成一个字母
			sb.append(s);//把字符添加到sb中
			float x = i*1.0F* w / 8;
			g2.setFont(randomFont());//设置随机字体
			g2.setColor(randomColor());//设置随机颜色
			g2.drawString(s, x+30, h-20);//画图
		}
		this.text = sb.toString();
		drawLine(image);//添加干扰线
		return image;
	}
	//返回验证码图片上的文本
	public String getText() {
		return text;
	}
	//保存图片到指定的输出流
	public static void output(BufferedImage image , OutputStream out) throws IOException{
		ImageIO.write(image, "JPEG", out);
	}
}